A number of processes, such as a number of manufacturing processes, require cooling. For example, a workpiece may need to be cooled in order to be properly formed or straightened. Similarly, a bit, such as a drill bit or a bit used for welding applications, such as friction-stir welding, may need to be cooled during use. In order to provide for such cooling, a coolant, such as water, is frequently placed in thermal contact with the workpiece, the tool or the like.
For example, metallic plates, such as those formed of steel, may be thermally formed or straightened. In this regard, a metallic plate may be heated, such as by means of an induction head, and thereafter bent or straightened, as desired. In order to initiate the bending or straightening process, the heated, metallic plate is quenched with a considerable amount of water. By quenching the metallic plate, the metal matrix recrystallizes which causes the metallic plate to bend or be straightened, as desired.
Similarly, tools, such as bits, generally experience an increase in temperature during use. With respect to a drill bit or a bit for use in welding applications, such as friction-stir welding applications, coolant, such as water, is commonly sprayed on or circulated through channels in such bits in order to cool the bits and permit continued machining.
Relatively cool water is typically utilized in these applications. Cooling is therefore provided by heat transfer from the workpiece or tool to the water which increases the temperature of the water. The cooling provided by such conventional techniques is not very quick, however, since the temperature of one gram of water increases by 1° C. in response to transfer of only one calorie of heat. In a number of applications, it would be advantageous to more quickly transfer heat from a workpiece or tool to the coolant, thereby potentially reducing thermal limitations that are otherwise imposed upon the underlying process.